SQLAlchemy 2.0 Support

Primarily remove the workaround added in
Ia6d512ff2ae417bab938cb095fbb0884d195010a which added
continued use of autocommit, which is incompatible with
SQLAlchemy 2.0.

Also set the environment for unit tests to report compatability
warnings, although it appears none are being reported at this time.

Also cuts out the db upgrade cruft to only use the online database
migration code through oslo_db's enginefacade, which has the smarts
to handle online or offline migrations.

And then, retools unit/functional test data storage to utlize sqlite,
and in that re-tooled the queries to prevent locking conditions
which could exist with queries, and some additional refactoring/cleanup.

Also, don't mock and test time.sleep().

Additionally, it looks like we have discovered the root cause of the
memory/connection leakage issue which has been observed, due to the
way lists of nodes are processed/returned.

This change was based upon the work in
I506da42a9891a245831f325e34bec92e0a3f33f0 which is included in
this commit as the entire database structure and interaction
has been modified for ironic-inspector.

Co-Authored-By: aarefiev <aarefiev@mirantis.com>
Story: 2009727
Task: 44132
Change-Id: Ic88eb9dec5fddc924a72d9a23c17a304954ebf46

ironic_inspector/cmd/dbsync.py

@@ -60,7 +60,7 @@ def add_command_parsers(subparsers):
 
 def _get_alembic_config():
     base_path = os.path.split(os.path.dirname(__file__))[0]
-    return alembic_config.Config(os.path.join(base_path, 'alembic.ini'))
+    return alembic_config.Config(os.path.join(base_path, 'db/alembic.ini'))
 
 
 def do_revision(config, cmd, *args, **kwargs):
@@ -85,7 +85,7 @@ def main(args=sys.argv[1:]):
     CONF.register_cli_opt(command_opt)
     CONF(args, project='ironic-inspector')
     config = _get_alembic_config()
-    config.set_main_option('script_location', "ironic_inspector:migrations")
+    config.set_main_option('script_location', "ironic_inspector.db:migrations")
     config.ironic_inspector_config = CONF
 
     CONF.command.func(config, CONF.command.name)

ironic_inspector/conductor/manager.py

@@ -28,7 +28,7 @@
 from ironic_inspector.common.i18n import _
 from ironic_inspector.common import ironic as ir_utils
 from ironic_inspector.common import keystone
-from ironic_inspector import db
+from ironic_inspector.db import api as dbapi
 from ironic_inspector import introspect
 from ironic_inspector import node_cache
 from ironic_inspector.plugins import base as plugins_base
@@ -52,6 +52,7 @@ def __init__(self):
         self._zeroconf = None
         self._shutting_down = semaphore.Semaphore()
         self.coordinator = None
+        self.dbapi = None
 
     def init_host(self):
         """Initialize Worker host
@@ -69,7 +70,8 @@ def init_host(self):
             LOG.info('Introspection data will be stored in the %s backend',
                      CONF.processing.store_data)
 
-        db.init()
+        if not self.dbapi:
+            self.dbapi = dbapi.init()
 
         self.coordinator = None
         try:
@@ -169,6 +171,8 @@ def del_host(self):
             self._zeroconf.close()
             self._zeroconf = None
 
+        self.dbapi = None
+
         self._shutting_down.release()
 
         LOG.info('Shut down successfully')

ironic_inspector/db/__init__.py

@@ -0,0 +1,19 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from oslo_db.sqlalchemy import enginefacade
+
+# TODO(aarefiev): enable foreign keys for SQLite once all unit
+#                 tests with failed constraint will be fixed.
+# FIXME(stephenfin): we need to remove reliance on autocommit semantics ASAP
+# since it's not compatible with SQLAlchemy 2.0
+enginefacade.configure(sqlite_fk=False)